This invention relates to systems for immobilizing a patient immediately prior to receiving radiation therapy, and in particular to a system and method that is adjustable for the head and neck, chest, or pelvis areas of the patient.
Radiotherapy has today become increasingly more precise, this greater precision necessitating reliable patient immobilizing systems. Typically patients undergoing radiation therapy for tumors and other conditions receive small doses of radiation repeatedly, often over extended periods of time. It is important to the success of the treatment for the patient to be comfortably repositioned accurately for these numerous treatment periods.
Past attempts by clinicians to position patients involved laser beams aimed at skin marks drawn on the patient, then immobilizing the patient with adhesive tape, plaster of paris, or strips of VELCRO (a registered trademark of VELCRO USA). These techniques were time consuming for the clinician and caused unsightly skin marks and adhesive tape irritation for the patient. In addition, these methods were difficult to perform on very young, old, or confused patients.
In recent years more precise and comfortable positioning and immobilization devices have been employed, fabricated from wood or plastic materials, plaster or fiberglass bandage materials, vacuum formed high temperature plastics, hand formable low temperature plastics, bite blocks, foamed in place urethane shells, and vacuum bags filled with polystyrene pellets which shape to the patient. For example, in current practice a hand formable thermoplastic material such as AQUAPLAST (a registered trademark of WFR Aquaplast Corporation) creates a customized anterior mold (a mold interposed on the skin of the patient between the patient and the source of radiation) of a portion of the patient, such as the face, chest, or pelvis area. This anterior mold is often used with a posterior mold (a mold in the shape of the patients head and neck, chest area, and so on, with the body of the patient positioned between this posterior mold and the source of radiation) acting as a mattress for comfortably supporting the patient during treatment. This posterior mold can be fabricated using a urethane foam to cast a body impression, or by use of a flexible vacuum bag containing pellets, such as polystyrene, which, when subjected to a vacuum, cause the shape of the patient to be formed in the vacuum bag.
While these current devices and techniques provide greater patient comfort and accuracy in patient repositioning prior to radiation therapy, they do not address the unique system and method of the instant invention for anchoring differently sized anterior and posterior molds together for fast, comfortable, and economical patient repositioning during radiation therapy.
It is therefore a primary object of the invention to provide an adjustable anchor for securing anterior and posterior molds to a patient for accurate repositioning of said patient during radiation therapy.
An additional object of the invention is to provide a single device for anchoring anterior and posterior molds for head and neck, chest, or pelvic patient immobilization set ups.
A further object of the invention is to provide a compatible device for anchoring virtually all currently available patient immobilization devices.
Another object of the invention is to provide a compatible anchoring device to provide a simple, inexpensive upgrade to achieve greater precision for existing immobilization equipment.
Still another object of the invention is to simplify immobilization equipment requirements for new or expanding treatment facilities so as to reduce capital expenditure for more specialized equipment.
A further object of the invention is to provide an adjustable anchor for customized anterior and posterior molds, said anchor providing for quick patient release to prevent patient injury during difficult or emergency treatment situations.